Hydrodynamically consistent many-body Harada-Sasa relation

Ramin Golestanian

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arXiv · 2406.16761

Hydrodynamically consistent many-body Harada-Sasa relation

Ramin Golestanian

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Abstract

The effect of hydrodynamic interactions on the non-equilibrium stochastic dynamics of particles -- arising from the conservation of momentum in the fluid medium -- is examined in the context of the relationship between fluctuations, response functions, and the entropy production rate. The multiplicative nature of the hydrodynamic interactions is shown to introduce subtleties that preclude a straightforward extension of the Harada-Sasa relation. A generalization of the definitions involved in the framework is used to propose a new form of the relation applicable to systems with hydrodynamic interactions. The resulting framework will enable characterization of the non-equilibrium properties of living and active matter systems, which are predominantly in suspensions.

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Ramin Golestanian. 2024-06-24. Hydrodynamically consistent many-body Harada-Sasa relation. https://arxiv.org/abs/2406.16761

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